Labs cleared in cancer report

By MARTIN JOHNSTON

The first comprehensive audit of women with cervical cancer has given laboratories a pass mark, but found flaws in other parts of the screening programme, especially how it serves Maori and poor people.

The long-awaited Auckland University audit, made public yesterday, found no evidence of systemic under-reporting by laboratories of high-grade cervical smears between 1996 and 2002, largely answering a question posed by an earlier inquiry.

The Health Ministry commissioned the $3 million audit following the recommendation of the Gisborne inquiry in 2001 into smear under-reporting in the region.

Dozens of women developed cancer and some died after their smear results were misread by pathologist Dr Michael Bottrill's laboratory and the failures were not picked up by the screening programme.

The inquiry committee, led by Ailsa Duffy, QC, said it "cannot be satisfied that the systemic problems have not resulted in unacceptable under-reporting in other regions".

Health Minister Annette King said the audit showed women could have confidence in the cervical screening programme.

Medical Association chairwoman Dr Tricia Briscoe agreed, but said the programme's funding priorities needed to shift in favour of Maori.

The College of GPs said the small fee women paid for screening was a barrier, suggesting better state funding was needed so the payment could be scrapped.

The audit reviewed the screening histories of 371 women diagnosed with invasive cervical cancer between January 2000 and September 2002.

Smear slides from 178 of the women, originally taken between six weeks and four years before diagnosis, were sent to an Australian laboratory for re-reading. They were spread among more than 4000 slides - most from women without cancer - to mimic normal laboratory practice.

The re-reading found 18 per cent of smears, originally read as negative in New Zealand, had high-grade abnormal cells. But this was below what the audit team called its "conservative" acceptable upper limit of 20 per cent.

"False negatives" are inherent in disease screening and the audit report says they are not uncommon before cervical cancer diagnosis "because of the fairly low sensitivity of a single smear".

"Of the women in the audit who had a screening smear in the six to 42 months prior to diagnosis 61 per cent had only negative smears." This was consistent with United States research.

The main problems identified by the auditors were:

* Only 20 per cent of the women with cervical cancer had been regularly screened.

* Just 50 per cent - and 42 per cent of Maori - had had a smear in the three-year period up to six months before diagnosis.

* For 21 per cent of Maori it took more than six months from their first high-grade smear until they were diagnosed, compared with 10 per cent of non-Maori.

The Maori death rate from cervical cancer is four times the non-Maori rate. The reasons are unknown.

The ministry's deputy director-general for public health, Don Matheson, said the lower participation rate and follow-up speed for Maori needed investigation.

He said likely factors were a person's available time, the priority they assigned to health care, money and whether they felt safe or whakama (shy or embarrassed).

The ministry needed to consider the report in more detail before commenting on its recommendations.

THE STORY SO FAR

2001: Gisborne ministerial inquiry calls for an audit of cervical cancer cases. It also says researchers must be allowed to see the health records of women enrolled in the cervical screening programme, without their consent.

March 2004: Parliament passes a law that will from next March allow evaluators to check the relevant health records, including GP files, of enrolled women without their consent.

Yesterday: Auckland University releases the results of the first national cervical cancer audit, done with the consent of participants.

Ministry of Health:
Cervical cancer audit report [PDF 211p 735kb]